Process of lubricating refrigerating-machines



(-No Model.)

' S. S.. 8v C. W. MILES.

PROGBSS 0F lLUBRmATIlsIG. RBFRIGERATING MACHINES. No. 525,224. PatentedAug. 28, 1894. c

I Ml

' WUQ/vl/{Sow 212421229212 @222222222 lCASPER W. MILES, citizens of theUnited UNITED` 'STATES PATENT ora-CE.

STEPHEN s. MILES AND CASPER w. MILES, CE CINCINNATI, CI-IIo.

PROCESS OF LUBRICATING REFRlGERATlNG-MACHINES.

SPECIFICATION forming part of Letters Patent No. 525,224, dated .August28, 1894.

l Application filed August 27,1892. Serial No. 444,320- (No specimens.)

To all whom t may concern:

Beit known that we, STEPHEN S. MILES and States, residing at Cincinnati,in the county of Hamilton and State of Ohio, have invented. certain newand useful Improvements in Processes of Lubricating RefrigeratingMachines, of which the following is a specication.

Our invention relates to an improved process of lubricatingrefrigerating machines. Its object is to secure an automatic circulationand constant feed of oil to the compressor to lubricate the operativeparts and seal the valves and stufling boxes.

In the accompanying drawings forming part of this specification, Figurel, represents a diagram of the compressor and system of condensing andrefrigerating pipes. Fig. 2, is a detail of a section of the pipe. Fig.3, is a detail modilication of Fig. l.

A represents the compressor pump, which may be of any approved pattern.

B represents a system of condensing pipes submerged in tank C ofcoolingwater.

c represents the water supply pipe, and c the overiiow. i

D represents a receiver into which the liquelied gas iiows from thecondenser.

d is the expansion valve.

E represents the system of refrigerating pipes, preferably submerged ina tank of brine F.

The system of pipes B, E, are arranged preferably so as to present acontinuous incline so that the pipes B drain the products ofcondensation into the receptacle D, and the pipes E drain any liquid toa point G near the pump intake.

The condenser is preferably raised above the level of the refrigeratingtank; this is not necessary however as the pressure inthe condensingcoil will force the liquefied gas from the receiver D to a sufficientheight to discharge it at the top of the refrigerating tank, when theyare both set upon-the same level.

The process of lubricating the compressor consists in charging thereceiver D with a mixture of liquefied gas, preferably sulphurous oxideand a light 'hydro-carbon oil, say from one half percent. to veper-cent. of oil. The proportions maybe varied however according to thedemands of dierent compressors. The oil used is preferably a purepetroleum oil sufficiently light so that it will not congeal at thetemperature of the expanding gas in the refrigerator pipes. In practicewe have found an oil of specific gravity 0.860 to answer the purpose.

The operation is as follows: The receiver D is charged with themixed-liquefied gas and oil in the proper proportions' (a small percentfage of oil readily forming a mechanical mixture with the liquefied gas),the pump is started and the expansion val-ve opened. As the mixture ofgas and oil is discharged into the refrigerating pipes, the gaslvaporizes f while the oil is deposited in a liquid form upon the insideof thep'ipe. The oil slowly flows, or is forced by the current ofvaporized gas down the incline of the pipe, and accumulates at a pointG,as indicated in Fig. 2, from whence rit is forced on to the pump bythe rapid current of the vapor or gas on its Way to the compressor.

In practice we have found the current of expanded vaporor gassufticient'to carry the oil through the refrigerating pipes whetherconstructed on an incline'or not, but the form shown is preferablewhere, by reason of a number of separate pipes E being employed, theforce of the current is not sufficient to, carry the oil along thepipes. If preferred' the incline of the refrigerating pipes E may bemaintained all the way to the intake of the compressor either by raisingthe refrigerating tank to the level of the pump intake, or by placingthe pump on a lower level as indicated in Fig. 3.

The oil and gas pass into the compressor, one as a liquid and the othera gas, and at a very low temperature. Under the action of thecompressor, however, the temperature of the gas is raised, and beinggradually imparted to the small body of oil accumulated uponthe`pressure silde of the pump vaporizes a portion" of it at each strokeof the pump, while fresh cool oil from the opposite end of the pumptakes itsplace, thus sufficient oil is maintained in the pump tolubricate it and for sealing purposes, while the excess is vaporized andpasses with the compressed gas to the condenser where both oil and gasare condensed to a combined liquid and pass to the receiver to be againusedl in the refrigerator.

The process herein described is distinguished from that in which anon-volatile liquid is used in connection with `a volatile liquid, suchas glycerine in connection with ammonia in which the glycerineis used toabsorb and condense the refrigerant.

We use sulphurous oxide and a Volatile oil which are refrigeratingliquids of dier-r ent densities,the hydrocarbon condensing in therefrigerator at the Working temperature and passing through therefrigerating coils Without congealing or interfering with the passageof the gas, entering the pump while at a low temperature, and yetvaporizing and passing to the condenser with the gas. Thus `only a smallpercentage of lubricant is employed, and it entirely obviates thenecessity of traps as its presence does notinterfere with the process ofrefrigeration while the machine may be run continuously without overheating the pump, or obstructing the passage of the gas.

The advantages of oil in compressor are two fold, rst it lubricates theplunger and piston rods, second it seals the valves and stuffing boxes.

By means of our process a steady oW of a small amount of oil isautomatically obtained,

2. The process of lubricating refrigerating machines, which consists inmixing with the refrigerant a sufficient quantity of light hydrocarbonoil to serve the purpose of lubrication, passing said mixture to asuitable expanding chamber, utilizing the oil at l'oW teinperature as alubricant inthe compressor,

and then asit volatilizes passing the sametogether With the refrigerantto the condenser Where the two are recoudensed to be used again,substantially as specified.

In testimony whereof We have hereunto set our hands.

STEPHEN S. MILES. C. W. MILES. Witnesses:

W. S. STUCKENBERG, O. KAISER.

